Merge tag 'pwm/for-4.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry...

[mirror_ubuntu-artful-kernel.git] / drivers / tty / serial / rp2.c

/*
 * Driver for Comtrol RocketPort EXPRESS/INFINITY cards
 *
 * Copyright (C) 2012 Kevin Cernekee <cernekee@gmail.com>
 *
 * Inspired by, and loosely based on:
 *
 *   ar933x_uart.c
 *     Copyright (C) 2011 Gabor Juhos <juhosg@openwrt.org>
 *
 *   rocketport_infinity_express-linux-1.20.tar.gz
 *     Copyright (C) 2004-2011 Comtrol, Inc.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 as published
 * by the Free Software Foundation.
 */

#include <linux/bitops.h>
#include <linux/compiler.h>
#include <linux/completion.h>
#include <linux/console.h>
#include <linux/delay.h>
#include <linux/firmware.h>
#include <linux/init.h>
#include <linux/io.h>
#include <linux/ioport.h>
#include <linux/irq.h>
#include <linux/kernel.h>
#include <linux/log2.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/serial.h>
#include <linux/serial_core.h>
#include <linux/slab.h>
#include <linux/sysrq.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include <linux/types.h>

#define DRV_NAME                        "rp2"

#define RP2_FW_NAME                     "rp2.fw"
#define RP2_UCODE_BYTES                 0x3f

#define PORTS_PER_ASIC                  16
#define ALL_PORTS_MASK                  (BIT(PORTS_PER_ASIC) - 1)

#define UART_CLOCK                      44236800
#define DEFAULT_BAUD_DIV                (UART_CLOCK / (9600 * 16))
#define FIFO_SIZE                       512

/* BAR0 registers */
#define RP2_FPGA_CTL0                   0x110
#define RP2_FPGA_CTL1                   0x11c
#define RP2_IRQ_MASK                    0x1ec
#define RP2_IRQ_MASK_EN_m               BIT(0)
#define RP2_IRQ_STATUS                  0x1f0

/* BAR1 registers */
#define RP2_ASIC_SPACING                0x1000
#define RP2_ASIC_OFFSET(i)              ((i) << ilog2(RP2_ASIC_SPACING))

#define RP2_PORT_BASE                   0x000
#define RP2_PORT_SPACING                0x040

#define RP2_UCODE_BASE                  0x400
#define RP2_UCODE_SPACING               0x80

#define RP2_CLK_PRESCALER               0xc00
#define RP2_CH_IRQ_STAT                 0xc04
#define RP2_CH_IRQ_MASK                 0xc08
#define RP2_ASIC_IRQ                    0xd00
#define RP2_ASIC_IRQ_EN_m               BIT(20)
#define RP2_GLOBAL_CMD                  0xd0c
#define RP2_ASIC_CFG                    0xd04

/* port registers */
#define RP2_DATA_DWORD                  0x000

#define RP2_DATA_BYTE                   0x008
#define RP2_DATA_BYTE_ERR_PARITY_m      BIT(8)
#define RP2_DATA_BYTE_ERR_OVERRUN_m     BIT(9)
#define RP2_DATA_BYTE_ERR_FRAMING_m     BIT(10)
#define RP2_DATA_BYTE_BREAK_m           BIT(11)

/* This lets uart_insert_char() drop bytes received on a !CREAD port */
#define RP2_DUMMY_READ                  BIT(16)

#define RP2_DATA_BYTE_EXCEPTION_MASK    (RP2_DATA_BYTE_ERR_PARITY_m | \
                                         RP2_DATA_BYTE_ERR_OVERRUN_m | \
                                         RP2_DATA_BYTE_ERR_FRAMING_m | \
                                         RP2_DATA_BYTE_BREAK_m)

#define RP2_RX_FIFO_COUNT               0x00c
#define RP2_TX_FIFO_COUNT               0x00e

#define RP2_CHAN_STAT                   0x010
#define RP2_CHAN_STAT_RXDATA_m          BIT(0)
#define RP2_CHAN_STAT_DCD_m             BIT(3)
#define RP2_CHAN_STAT_DSR_m             BIT(4)
#define RP2_CHAN_STAT_CTS_m             BIT(5)
#define RP2_CHAN_STAT_RI_m              BIT(6)
#define RP2_CHAN_STAT_OVERRUN_m         BIT(13)
#define RP2_CHAN_STAT_DSR_CHANGED_m     BIT(16)
#define RP2_CHAN_STAT_CTS_CHANGED_m     BIT(17)
#define RP2_CHAN_STAT_CD_CHANGED_m      BIT(18)
#define RP2_CHAN_STAT_RI_CHANGED_m      BIT(22)
#define RP2_CHAN_STAT_TXEMPTY_m         BIT(25)

#define RP2_CHAN_STAT_MS_CHANGED_MASK   (RP2_CHAN_STAT_DSR_CHANGED_m | \
                                         RP2_CHAN_STAT_CTS_CHANGED_m | \
                                         RP2_CHAN_STAT_CD_CHANGED_m | \
                                         RP2_CHAN_STAT_RI_CHANGED_m)

#define RP2_TXRX_CTL                    0x014
#define RP2_TXRX_CTL_MSRIRQ_m           BIT(0)
#define RP2_TXRX_CTL_RXIRQ_m            BIT(2)
#define RP2_TXRX_CTL_RX_TRIG_s          3
#define RP2_TXRX_CTL_RX_TRIG_m          (0x3 << RP2_TXRX_CTL_RX_TRIG_s)
#define RP2_TXRX_CTL_RX_TRIG_1          (0x1 << RP2_TXRX_CTL_RX_TRIG_s)
#define RP2_TXRX_CTL_RX_TRIG_256        (0x2 << RP2_TXRX_CTL_RX_TRIG_s)
#define RP2_TXRX_CTL_RX_TRIG_448        (0x3 << RP2_TXRX_CTL_RX_TRIG_s)
#define RP2_TXRX_CTL_RX_EN_m            BIT(5)
#define RP2_TXRX_CTL_RTSFLOW_m          BIT(6)
#define RP2_TXRX_CTL_DTRFLOW_m          BIT(7)
#define RP2_TXRX_CTL_TX_TRIG_s          16
#define RP2_TXRX_CTL_TX_TRIG_m          (0x3 << RP2_TXRX_CTL_RX_TRIG_s)
#define RP2_TXRX_CTL_DSRFLOW_m          BIT(18)
#define RP2_TXRX_CTL_TXIRQ_m            BIT(19)
#define RP2_TXRX_CTL_CTSFLOW_m          BIT(23)
#define RP2_TXRX_CTL_TX_EN_m            BIT(24)
#define RP2_TXRX_CTL_RTS_m              BIT(25)
#define RP2_TXRX_CTL_DTR_m              BIT(26)
#define RP2_TXRX_CTL_LOOP_m             BIT(27)
#define RP2_TXRX_CTL_BREAK_m            BIT(28)
#define RP2_TXRX_CTL_CMSPAR_m           BIT(29)
#define RP2_TXRX_CTL_nPARODD_m          BIT(30)
#define RP2_TXRX_CTL_PARENB_m           BIT(31)

#define RP2_UART_CTL                    0x018
#define RP2_UART_CTL_MODE_s             0
#define RP2_UART_CTL_MODE_m             (0x7 << RP2_UART_CTL_MODE_s)
#define RP2_UART_CTL_MODE_rs232         (0x1 << RP2_UART_CTL_MODE_s)
#define RP2_UART_CTL_FLUSH_RX_m         BIT(3)
#define RP2_UART_CTL_FLUSH_TX_m         BIT(4)
#define RP2_UART_CTL_RESET_CH_m         BIT(5)
#define RP2_UART_CTL_XMIT_EN_m          BIT(6)
#define RP2_UART_CTL_DATABITS_s         8
#define RP2_UART_CTL_DATABITS_m         (0x3 << RP2_UART_CTL_DATABITS_s)
#define RP2_UART_CTL_DATABITS_8         (0x3 << RP2_UART_CTL_DATABITS_s)
#define RP2_UART_CTL_DATABITS_7         (0x2 << RP2_UART_CTL_DATABITS_s)
#define RP2_UART_CTL_DATABITS_6         (0x1 << RP2_UART_CTL_DATABITS_s)
#define RP2_UART_CTL_DATABITS_5         (0x0 << RP2_UART_CTL_DATABITS_s)
#define RP2_UART_CTL_STOPBITS_m         BIT(10)

#define RP2_BAUD                        0x01c

/* ucode registers */
#define RP2_TX_SWFLOW                   0x02
#define RP2_TX_SWFLOW_ena               0x81
#define RP2_TX_SWFLOW_dis               0x9d

#define RP2_RX_SWFLOW                   0x0c
#define RP2_RX_SWFLOW_ena               0x81
#define RP2_RX_SWFLOW_dis               0x8d

#define RP2_RX_FIFO                     0x37
#define RP2_RX_FIFO_ena                 0x08
#define RP2_RX_FIFO_dis                 0x81

static struct uart_driver rp2_uart_driver = {
        .owner                          = THIS_MODULE,
        .driver_name                    = DRV_NAME,
        .dev_name                       = "ttyRP",
        .nr                             = CONFIG_SERIAL_RP2_NR_UARTS,
};

struct rp2_card;

struct rp2_uart_port {
        struct uart_port                port;
        int                             idx;
        int                             ignore_rx;
        struct rp2_card                 *card;
        void __iomem                    *asic_base;
        void __iomem                    *base;
        void __iomem                    *ucode;
};

struct rp2_card {
        struct pci_dev                  *pdev;
        struct rp2_uart_port            *ports;
        int                             n_ports;
        int                             initialized_ports;
        int                             minor_start;
        int                             smpte;
        void __iomem                    *bar0;
        void __iomem                    *bar1;
        spinlock_t                      card_lock;
        struct completion               fw_loaded;
};

#define RP_ID(prod) PCI_VDEVICE(RP, (prod))
#define RP_CAP(ports, smpte) (((ports) << 8) | ((smpte) << 0))

static inline void rp2_decode_cap(const struct pci_device_id *id,
                                  int *ports, int *smpte)
{
        *ports = id->driver_data >> 8;
        *smpte = id->driver_data & 0xff;
}

static DEFINE_SPINLOCK(rp2_minor_lock);
static int rp2_minor_next;

static int rp2_alloc_ports(int n_ports)
{
        int ret = -ENOSPC;

        spin_lock(&rp2_minor_lock);
        if (rp2_minor_next + n_ports <= CONFIG_SERIAL_RP2_NR_UARTS) {
                /* sorry, no support for hot unplugging individual cards */
                ret = rp2_minor_next;
                rp2_minor_next += n_ports;
        }
        spin_unlock(&rp2_minor_lock);

        return ret;
}

static inline struct rp2_uart_port *port_to_up(struct uart_port *port)
{
        return container_of(port, struct rp2_uart_port, port);
}

static void rp2_rmw(struct rp2_uart_port *up, int reg,
                    u32 clr_bits, u32 set_bits)
{
        u32 tmp = readl(up->base + reg);
        tmp &= ~clr_bits;
        tmp |= set_bits;
        writel(tmp, up->base + reg);
}

static void rp2_rmw_clr(struct rp2_uart_port *up, int reg, u32 val)
{
        rp2_rmw(up, reg, val, 0);
}

static void rp2_rmw_set(struct rp2_uart_port *up, int reg, u32 val)
{
        rp2_rmw(up, reg, 0, val);
}

static void rp2_mask_ch_irq(struct rp2_uart_port *up, int ch_num,
                            int is_enabled)
{
        unsigned long flags, irq_mask;

        spin_lock_irqsave(&up->card->card_lock, flags);

        irq_mask = readl(up->asic_base + RP2_CH_IRQ_MASK);
        if (is_enabled)
                irq_mask &= ~BIT(ch_num);
        else
                irq_mask |= BIT(ch_num);
        writel(irq_mask, up->asic_base + RP2_CH_IRQ_MASK);

        spin_unlock_irqrestore(&up->card->card_lock, flags);
}

static unsigned int rp2_uart_tx_empty(struct uart_port *port)
{
        struct rp2_uart_port *up = port_to_up(port);
        unsigned long tx_fifo_bytes, flags;

        /*
         * This should probably check the transmitter, not the FIFO.
         * But the TXEMPTY bit doesn't seem to work unless the TX IRQ is
         * enabled.
         */
        spin_lock_irqsave(&up->port.lock, flags);
        tx_fifo_bytes = readw(up->base + RP2_TX_FIFO_COUNT);
        spin_unlock_irqrestore(&up->port.lock, flags);

        return tx_fifo_bytes ? 0 : TIOCSER_TEMT;
}

static unsigned int rp2_uart_get_mctrl(struct uart_port *port)
{
        struct rp2_uart_port *up = port_to_up(port);
        u32 status;

        status = readl(up->base + RP2_CHAN_STAT);
        return ((status & RP2_CHAN_STAT_DCD_m) ? TIOCM_CAR : 0) |
               ((status & RP2_CHAN_STAT_DSR_m) ? TIOCM_DSR : 0) |
               ((status & RP2_CHAN_STAT_CTS_m) ? TIOCM_CTS : 0) |
               ((status & RP2_CHAN_STAT_RI_m) ? TIOCM_RI : 0);
}

static void rp2_uart_set_mctrl(struct uart_port *port, unsigned int mctrl)
{
        rp2_rmw(port_to_up(port), RP2_TXRX_CTL,
                RP2_TXRX_CTL_DTR_m | RP2_TXRX_CTL_RTS_m | RP2_TXRX_CTL_LOOP_m,
                ((mctrl & TIOCM_DTR) ? RP2_TXRX_CTL_DTR_m : 0) |
                ((mctrl & TIOCM_RTS) ? RP2_TXRX_CTL_RTS_m : 0) |
                ((mctrl & TIOCM_LOOP) ? RP2_TXRX_CTL_LOOP_m : 0));
}

static void rp2_uart_start_tx(struct uart_port *port)
{
        rp2_rmw_set(port_to_up(port), RP2_TXRX_CTL, RP2_TXRX_CTL_TXIRQ_m);
}

static void rp2_uart_stop_tx(struct uart_port *port)
{
        rp2_rmw_clr(port_to_up(port), RP2_TXRX_CTL, RP2_TXRX_CTL_TXIRQ_m);
}

static void rp2_uart_stop_rx(struct uart_port *port)
{
        rp2_rmw_clr(port_to_up(port), RP2_TXRX_CTL, RP2_TXRX_CTL_RXIRQ_m);
}

static void rp2_uart_break_ctl(struct uart_port *port, int break_state)
{
        unsigned long flags;

        spin_lock_irqsave(&port->lock, flags);
        rp2_rmw(port_to_up(port), RP2_TXRX_CTL, RP2_TXRX_CTL_BREAK_m,
                break_state ? RP2_TXRX_CTL_BREAK_m : 0);
        spin_unlock_irqrestore(&port->lock, flags);
}

static void rp2_uart_enable_ms(struct uart_port *port)
{
        rp2_rmw_set(port_to_up(port), RP2_TXRX_CTL, RP2_TXRX_CTL_MSRIRQ_m);
}

static void __rp2_uart_set_termios(struct rp2_uart_port *up,
                                   unsigned long cfl,
                                   unsigned long ifl,
                                   unsigned int baud_div)
{
        /* baud rate divisor (calculated elsewhere).  0 = divide-by-1 */
        writew(baud_div - 1, up->base + RP2_BAUD);

        /* data bits and stop bits */
        rp2_rmw(up, RP2_UART_CTL,
                RP2_UART_CTL_STOPBITS_m | RP2_UART_CTL_DATABITS_m,
                ((cfl & CSTOPB) ? RP2_UART_CTL_STOPBITS_m : 0) |
                (((cfl & CSIZE) == CS8) ? RP2_UART_CTL_DATABITS_8 : 0) |
                (((cfl & CSIZE) == CS7) ? RP2_UART_CTL_DATABITS_7 : 0) |
                (((cfl & CSIZE) == CS6) ? RP2_UART_CTL_DATABITS_6 : 0) |
                (((cfl & CSIZE) == CS5) ? RP2_UART_CTL_DATABITS_5 : 0));

        /* parity and hardware flow control */
        rp2_rmw(up, RP2_TXRX_CTL,
                RP2_TXRX_CTL_PARENB_m | RP2_TXRX_CTL_nPARODD_m |
                RP2_TXRX_CTL_CMSPAR_m | RP2_TXRX_CTL_DTRFLOW_m |
                RP2_TXRX_CTL_DSRFLOW_m | RP2_TXRX_CTL_RTSFLOW_m |
                RP2_TXRX_CTL_CTSFLOW_m,
                ((cfl & PARENB) ? RP2_TXRX_CTL_PARENB_m : 0) |
                ((cfl & PARODD) ? 0 : RP2_TXRX_CTL_nPARODD_m) |
                ((cfl & CMSPAR) ? RP2_TXRX_CTL_CMSPAR_m : 0) |
                ((cfl & CRTSCTS) ? (RP2_TXRX_CTL_RTSFLOW_m |
                                    RP2_TXRX_CTL_CTSFLOW_m) : 0));

        /* XON/XOFF software flow control */
        writeb((ifl & IXON) ? RP2_TX_SWFLOW_ena : RP2_TX_SWFLOW_dis,
               up->ucode + RP2_TX_SWFLOW);
        writeb((ifl & IXOFF) ? RP2_RX_SWFLOW_ena : RP2_RX_SWFLOW_dis,
               up->ucode + RP2_RX_SWFLOW);
}

static void rp2_uart_set_termios(struct uart_port *port,
                                 struct ktermios *new,
                                 struct ktermios *old)
{
        struct rp2_uart_port *up = port_to_up(port);
        unsigned long flags;
        unsigned int baud, baud_div;

        baud = uart_get_baud_rate(port, new, old, 0, port->uartclk / 16);
        baud_div = uart_get_divisor(port, baud);

        if (tty_termios_baud_rate(new))
                tty_termios_encode_baud_rate(new, baud, baud);

        spin_lock_irqsave(&port->lock, flags);

        /* ignore all characters if CREAD is not set */
        port->ignore_status_mask = (new->c_cflag & CREAD) ? 0 : RP2_DUMMY_READ;

        __rp2_uart_set_termios(up, new->c_cflag, new->c_iflag, baud_div);
        uart_update_timeout(port, new->c_cflag, baud);

        spin_unlock_irqrestore(&port->lock, flags);
}

static void rp2_rx_chars(struct rp2_uart_port *up)
{
        u16 bytes = readw(up->base + RP2_RX_FIFO_COUNT);
        struct tty_port *port = &up->port.state->port;

        for (; bytes != 0; bytes--) {
                u32 byte = readw(up->base + RP2_DATA_BYTE) | RP2_DUMMY_READ;
                char ch = byte & 0xff;

                if (likely(!(byte & RP2_DATA_BYTE_EXCEPTION_MASK))) {
                        if (!uart_handle_sysrq_char(&up->port, ch))
                                uart_insert_char(&up->port, byte, 0, ch,
                                                 TTY_NORMAL);
                } else {
                        char flag = TTY_NORMAL;

                        if (byte & RP2_DATA_BYTE_BREAK_m)
                                flag = TTY_BREAK;
                        else if (byte & RP2_DATA_BYTE_ERR_FRAMING_m)
                                flag = TTY_FRAME;
                        else if (byte & RP2_DATA_BYTE_ERR_PARITY_m)
                                flag = TTY_PARITY;
                        uart_insert_char(&up->port, byte,
                                         RP2_DATA_BYTE_ERR_OVERRUN_m, ch, flag);
                }
                up->port.icount.rx++;
        }

        spin_unlock(&up->port.lock);
        tty_flip_buffer_push(port);
        spin_lock(&up->port.lock);
}

static void rp2_tx_chars(struct rp2_uart_port *up)
{
        u16 max_tx = FIFO_SIZE - readw(up->base + RP2_TX_FIFO_COUNT);
        struct circ_buf *xmit = &up->port.state->xmit;

        if (uart_tx_stopped(&up->port)) {
                rp2_uart_stop_tx(&up->port);
                return;
        }

        for (; max_tx != 0; max_tx--) {
                if (up->port.x_char) {
                        writeb(up->port.x_char, up->base + RP2_DATA_BYTE);
                        up->port.x_char = 0;
                        up->port.icount.tx++;
                        continue;
                }
                if (uart_circ_empty(xmit)) {
                        rp2_uart_stop_tx(&up->port);
                        break;
                }
                writeb(xmit->buf[xmit->tail], up->base + RP2_DATA_BYTE);
                xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
                up->port.icount.tx++;
        }

        if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
                uart_write_wakeup(&up->port);
}

static void rp2_ch_interrupt(struct rp2_uart_port *up)
{
        u32 status;

        spin_lock(&up->port.lock);

        /*
         * The IRQ status bits are clear-on-write.  Other status bits in
         * this register aren't, so it's harmless to write to them.
         */
        status = readl(up->base + RP2_CHAN_STAT);
        writel(status, up->base + RP2_CHAN_STAT);

        if (status & RP2_CHAN_STAT_RXDATA_m)
                rp2_rx_chars(up);
        if (status & RP2_CHAN_STAT_TXEMPTY_m)
                rp2_tx_chars(up);
        if (status & RP2_CHAN_STAT_MS_CHANGED_MASK)
                wake_up_interruptible(&up->port.state->port.delta_msr_wait);

        spin_unlock(&up->port.lock);
}

static int rp2_asic_interrupt(struct rp2_card *card, unsigned int asic_id)
{
        void __iomem *base = card->bar1 + RP2_ASIC_OFFSET(asic_id);
        int ch, handled = 0;
        unsigned long status = readl(base + RP2_CH_IRQ_STAT) &
                               ~readl(base + RP2_CH_IRQ_MASK);

        for_each_set_bit(ch, &status, PORTS_PER_ASIC) {
                rp2_ch_interrupt(&card->ports[ch]);
                handled++;
        }
        return handled;
}

static irqreturn_t rp2_uart_interrupt(int irq, void *dev_id)
{
        struct rp2_card *card = dev_id;
        int handled;

        handled = rp2_asic_interrupt(card, 0);
        if (card->n_ports >= PORTS_PER_ASIC)
                handled += rp2_asic_interrupt(card, 1);

        return handled ? IRQ_HANDLED : IRQ_NONE;
}

static inline void rp2_flush_fifos(struct rp2_uart_port *up)
{
        rp2_rmw_set(up, RP2_UART_CTL,
                    RP2_UART_CTL_FLUSH_RX_m | RP2_UART_CTL_FLUSH_TX_m);
        readl(up->base + RP2_UART_CTL);
        udelay(10);
        rp2_rmw_clr(up, RP2_UART_CTL,
                    RP2_UART_CTL_FLUSH_RX_m | RP2_UART_CTL_FLUSH_TX_m);
}

static int rp2_uart_startup(struct uart_port *port)
{
        struct rp2_uart_port *up = port_to_up(port);

        rp2_flush_fifos(up);
        rp2_rmw(up, RP2_TXRX_CTL, RP2_TXRX_CTL_MSRIRQ_m, RP2_TXRX_CTL_RXIRQ_m);
        rp2_rmw(up, RP2_TXRX_CTL, RP2_TXRX_CTL_RX_TRIG_m,
                RP2_TXRX_CTL_RX_TRIG_1);
        rp2_rmw(up, RP2_CHAN_STAT, 0, 0);
        rp2_mask_ch_irq(up, up->idx, 1);

        return 0;
}

static void rp2_uart_shutdown(struct uart_port *port)
{
        struct rp2_uart_port *up = port_to_up(port);
        unsigned long flags;

        rp2_uart_break_ctl(port, 0);

        spin_lock_irqsave(&port->lock, flags);
        rp2_mask_ch_irq(up, up->idx, 0);
        rp2_rmw(up, RP2_CHAN_STAT, 0, 0);
        spin_unlock_irqrestore(&port->lock, flags);
}

static const char *rp2_uart_type(struct uart_port *port)
{
        return (port->type == PORT_RP2) ? "RocketPort 2 UART" : NULL;
}

static void rp2_uart_release_port(struct uart_port *port)
{
        /* Nothing to release ... */
}

static int rp2_uart_request_port(struct uart_port *port)
{
        /* UARTs always present */
        return 0;
}

static void rp2_uart_config_port(struct uart_port *port, int flags)
{
        if (flags & UART_CONFIG_TYPE)
                port->type = PORT_RP2;
}

static int rp2_uart_verify_port(struct uart_port *port,
                                   struct serial_struct *ser)
{
        if (ser->type != PORT_UNKNOWN && ser->type != PORT_RP2)
                return -EINVAL;

        return 0;
}

static const struct uart_ops rp2_uart_ops = {
        .tx_empty       = rp2_uart_tx_empty,
        .set_mctrl      = rp2_uart_set_mctrl,
        .get_mctrl      = rp2_uart_get_mctrl,
        .stop_tx        = rp2_uart_stop_tx,
        .start_tx       = rp2_uart_start_tx,
        .stop_rx        = rp2_uart_stop_rx,
        .enable_ms      = rp2_uart_enable_ms,
        .break_ctl      = rp2_uart_break_ctl,
        .startup        = rp2_uart_startup,
        .shutdown       = rp2_uart_shutdown,
        .set_termios    = rp2_uart_set_termios,
        .type           = rp2_uart_type,
        .release_port   = rp2_uart_release_port,
        .request_port   = rp2_uart_request_port,
        .config_port    = rp2_uart_config_port,
        .verify_port    = rp2_uart_verify_port,
};

static void rp2_reset_asic(struct rp2_card *card, unsigned int asic_id)
{
        void __iomem *base = card->bar1 + RP2_ASIC_OFFSET(asic_id);
        u32 clk_cfg;

        writew(1, base + RP2_GLOBAL_CMD);
        readw(base + RP2_GLOBAL_CMD);
        msleep(100);
        writel(0, base + RP2_CLK_PRESCALER);

        /* TDM clock configuration */
        clk_cfg = readw(base + RP2_ASIC_CFG);
        clk_cfg = (clk_cfg & ~BIT(8)) | BIT(9);
        writew(clk_cfg, base + RP2_ASIC_CFG);

        /* IRQ routing */
        writel(ALL_PORTS_MASK, base + RP2_CH_IRQ_MASK);
        writel(RP2_ASIC_IRQ_EN_m, base + RP2_ASIC_IRQ);
}

static void rp2_init_card(struct rp2_card *card)
{
        writel(4, card->bar0 + RP2_FPGA_CTL0);
        writel(0, card->bar0 + RP2_FPGA_CTL1);

        rp2_reset_asic(card, 0);
        if (card->n_ports >= PORTS_PER_ASIC)
                rp2_reset_asic(card, 1);

        writel(RP2_IRQ_MASK_EN_m, card->bar0 + RP2_IRQ_MASK);
}

static void rp2_init_port(struct rp2_uart_port *up, const struct firmware *fw)
{
        int i;

        writel(RP2_UART_CTL_RESET_CH_m, up->base + RP2_UART_CTL);
        readl(up->base + RP2_UART_CTL);
        udelay(1);

        writel(0, up->base + RP2_TXRX_CTL);
        writel(0, up->base + RP2_UART_CTL);
        readl(up->base + RP2_UART_CTL);
        udelay(1);

        rp2_flush_fifos(up);

        for (i = 0; i < min_t(int, fw->size, RP2_UCODE_BYTES); i++)
                writeb(fw->data[i], up->ucode + i);

        __rp2_uart_set_termios(up, CS8 | CREAD | CLOCAL, 0, DEFAULT_BAUD_DIV);
        rp2_uart_set_mctrl(&up->port, 0);

        writeb(RP2_RX_FIFO_ena, up->ucode + RP2_RX_FIFO);
        rp2_rmw(up, RP2_UART_CTL, RP2_UART_CTL_MODE_m,
                RP2_UART_CTL_XMIT_EN_m | RP2_UART_CTL_MODE_rs232);
        rp2_rmw_set(up, RP2_TXRX_CTL,
                    RP2_TXRX_CTL_TX_EN_m | RP2_TXRX_CTL_RX_EN_m);
}

static void rp2_remove_ports(struct rp2_card *card)
{
        int i;

        for (i = 0; i < card->initialized_ports; i++)
                uart_remove_one_port(&rp2_uart_driver, &card->ports[i].port);
        card->initialized_ports = 0;
}

static void rp2_fw_cb(const struct firmware *fw, void *context)
{
        struct rp2_card *card = context;
        resource_size_t phys_base;
        int i, rc = -ENOENT;

        if (!fw) {
                dev_err(&card->pdev->dev, "cannot find '%s' firmware image\n",
                        RP2_FW_NAME);
                goto no_fw;
        }

        phys_base = pci_resource_start(card->pdev, 1);

        for (i = 0; i < card->n_ports; i++) {
                struct rp2_uart_port *rp = &card->ports[i];
                struct uart_port *p;
                int j = (unsigned)i % PORTS_PER_ASIC;

                rp->asic_base = card->bar1;
                rp->base = card->bar1 + RP2_PORT_BASE + j*RP2_PORT_SPACING;
                rp->ucode = card->bar1 + RP2_UCODE_BASE + j*RP2_UCODE_SPACING;
                rp->card = card;
                rp->idx = j;

                p = &rp->port;
                p->line = card->minor_start + i;
                p->dev = &card->pdev->dev;
                p->type = PORT_RP2;
                p->iotype = UPIO_MEM32;
                p->uartclk = UART_CLOCK;
                p->regshift = 2;
                p->fifosize = FIFO_SIZE;
                p->ops = &rp2_uart_ops;
                p->irq = card->pdev->irq;
                p->membase = rp->base;
                p->mapbase = phys_base + RP2_PORT_BASE + j*RP2_PORT_SPACING;

                if (i >= PORTS_PER_ASIC) {
                        rp->asic_base += RP2_ASIC_SPACING;
                        rp->base += RP2_ASIC_SPACING;
                        rp->ucode += RP2_ASIC_SPACING;
                        p->mapbase += RP2_ASIC_SPACING;
                }

                rp2_init_port(rp, fw);
                rc = uart_add_one_port(&rp2_uart_driver, p);
                if (rc) {
                        dev_err(&card->pdev->dev,
                                "error registering port %d: %d\n", i, rc);
                        rp2_remove_ports(card);
                        break;
                }
                card->initialized_ports++;
        }

        release_firmware(fw);
no_fw:
        /*
         * rp2_fw_cb() is called from a workqueue long after rp2_probe()
         * has already returned success.  So if something failed here,
         * we'll just leave the now-dormant device in place until somebody
         * unbinds it.
         */
        if (rc)
                dev_warn(&card->pdev->dev, "driver initialization failed\n");

        complete(&card->fw_loaded);
}

static int rp2_probe(struct pci_dev *pdev,
                                   const struct pci_device_id *id)
{
        struct rp2_card *card;
        struct rp2_uart_port *ports;
        void __iomem * const *bars;
        int rc;

        card = devm_kzalloc(&pdev->dev, sizeof(*card), GFP_KERNEL);
        if (!card)
                return -ENOMEM;
        pci_set_drvdata(pdev, card);
        spin_lock_init(&card->card_lock);
        init_completion(&card->fw_loaded);

        rc = pcim_enable_device(pdev);
        if (rc)
                return rc;

        rc = pcim_iomap_regions_request_all(pdev, 0x03, DRV_NAME);
        if (rc)
                return rc;

        bars = pcim_iomap_table(pdev);
        card->bar0 = bars[0];
        card->bar1 = bars[1];
        card->pdev = pdev;

        rp2_decode_cap(id, &card->n_ports, &card->smpte);
        dev_info(&pdev->dev, "found new card with %d ports\n", card->n_ports);

        card->minor_start = rp2_alloc_ports(card->n_ports);
        if (card->minor_start < 0) {
                dev_err(&pdev->dev,
                        "too many ports (try increasing CONFIG_SERIAL_RP2_NR_UARTS)\n");
                return -EINVAL;
        }

        rp2_init_card(card);

        ports = devm_kzalloc(&pdev->dev, sizeof(*ports) * card->n_ports,
                             GFP_KERNEL);
        if (!ports)
                return -ENOMEM;
        card->ports = ports;

        rc = devm_request_irq(&pdev->dev, pdev->irq, rp2_uart_interrupt,
                              IRQF_SHARED, DRV_NAME, card);
        if (rc)
                return rc;

        /*
         * Only catastrophic errors (e.g. ENOMEM) are reported here.
         * If the FW image is missing, we'll find out in rp2_fw_cb()
         * and print an error message.
         */
        rc = request_firmware_nowait(THIS_MODULE, 1, RP2_FW_NAME, &pdev->dev,
                                     GFP_KERNEL, card, rp2_fw_cb);
        if (rc)
                return rc;
        dev_dbg(&pdev->dev, "waiting for firmware blob...\n");

        return 0;
}

static void rp2_remove(struct pci_dev *pdev)
{
        struct rp2_card *card = pci_get_drvdata(pdev);

        wait_for_completion(&card->fw_loaded);
        rp2_remove_ports(card);
}

static const struct pci_device_id rp2_pci_tbl[] = {

        /* RocketPort INFINITY cards */

        { RP_ID(0x0040), RP_CAP(8,  0) }, /* INF Octa, RJ45, selectable */
        { RP_ID(0x0041), RP_CAP(32, 0) }, /* INF 32, ext interface */
        { RP_ID(0x0042), RP_CAP(8,  0) }, /* INF Octa, ext interface */
        { RP_ID(0x0043), RP_CAP(16, 0) }, /* INF 16, ext interface */
        { RP_ID(0x0044), RP_CAP(4,  0) }, /* INF Quad, DB, selectable */
        { RP_ID(0x0045), RP_CAP(8,  0) }, /* INF Octa, DB, selectable */
        { RP_ID(0x0046), RP_CAP(4,  0) }, /* INF Quad, ext interface */
        { RP_ID(0x0047), RP_CAP(4,  0) }, /* INF Quad, RJ45 */
        { RP_ID(0x004a), RP_CAP(4,  0) }, /* INF Plus, Quad */
        { RP_ID(0x004b), RP_CAP(8,  0) }, /* INF Plus, Octa */
        { RP_ID(0x004c), RP_CAP(8,  0) }, /* INF III, Octa */
        { RP_ID(0x004d), RP_CAP(4,  0) }, /* INF III, Quad */
        { RP_ID(0x004e), RP_CAP(2,  0) }, /* INF Plus, 2, RS232 */
        { RP_ID(0x004f), RP_CAP(2,  1) }, /* INF Plus, 2, SMPTE */
        { RP_ID(0x0050), RP_CAP(4,  0) }, /* INF Plus, Quad, RJ45 */
        { RP_ID(0x0051), RP_CAP(8,  0) }, /* INF Plus, Octa, RJ45 */
        { RP_ID(0x0052), RP_CAP(8,  1) }, /* INF Octa, SMPTE */

        /* RocketPort EXPRESS cards */

        { RP_ID(0x0060), RP_CAP(8,  0) }, /* EXP Octa, RJ45, selectable */
        { RP_ID(0x0061), RP_CAP(32, 0) }, /* EXP 32, ext interface */
        { RP_ID(0x0062), RP_CAP(8,  0) }, /* EXP Octa, ext interface */
        { RP_ID(0x0063), RP_CAP(16, 0) }, /* EXP 16, ext interface */
        { RP_ID(0x0064), RP_CAP(4,  0) }, /* EXP Quad, DB, selectable */
        { RP_ID(0x0065), RP_CAP(8,  0) }, /* EXP Octa, DB, selectable */
        { RP_ID(0x0066), RP_CAP(4,  0) }, /* EXP Quad, ext interface */
        { RP_ID(0x0067), RP_CAP(4,  0) }, /* EXP Quad, RJ45 */
        { RP_ID(0x0068), RP_CAP(8,  0) }, /* EXP Octa, RJ11 */
        { RP_ID(0x0072), RP_CAP(8,  1) }, /* EXP Octa, SMPTE */
        { }
};
MODULE_DEVICE_TABLE(pci, rp2_pci_tbl);

static struct pci_driver rp2_pci_driver = {
        .name           = DRV_NAME,
        .id_table       = rp2_pci_tbl,
        .probe          = rp2_probe,
        .remove         = rp2_remove,
};

static int __init rp2_uart_init(void)
{
        int rc;

        rc = uart_register_driver(&rp2_uart_driver);
        if (rc)
                return rc;

        rc = pci_register_driver(&rp2_pci_driver);
        if (rc) {
                uart_unregister_driver(&rp2_uart_driver);
                return rc;
        }

        return 0;
}

static void __exit rp2_uart_exit(void)
{
        pci_unregister_driver(&rp2_pci_driver);
        uart_unregister_driver(&rp2_uart_driver);
}

module_init(rp2_uart_init);
module_exit(rp2_uart_exit);

MODULE_DESCRIPTION("Comtrol RocketPort EXPRESS/INFINITY driver");
MODULE_AUTHOR("Kevin Cernekee <cernekee@gmail.com>");
MODULE_LICENSE("GPL v2");
MODULE_FIRMWARE(RP2_FW_NAME);